Different rotorcraft bodies experience different levels of vibration. For example, a rotor system of a rotorcraft experiences periodic vibration due to the rotation of a rotor, while a fuselage of the rotorcraft experiences a vibration that is different from that experienced by the rotor system. A vibration isolation system is used in rotorcrafts such as helicopters and tiltrotor aircrafts to reduce or suppress vibration transmission between two bodies of a rotorcraft, for example, between the rotor system and the fuselage. A vibration isolation system sometimes includes one or more liquid inertia vibration eliminator (LIVE™) units connecting two bodies of a rotorcraft to reduce or cancel transmissibility of vibration between the two bodies. Sometimes, LIVE™ units can be characterized as passive LIVE™ units or active LIVE™ units.